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// 改造评论数据结构
// 递归
// 假如有一张纸厚度为0.0001米，折叠多少次可以超过10000米
/*let a = 0.0001
let num = 0
function fn() {
    a *= 2
    num++
    if(a < 10000) {
        fn()
    }
}

fn()
console.log(num)*/



let arr = [
    {comment_id: 1, user_id: 43, comment_date: "05-21", comment_content: "蜡笔小新很好看!", parent_id: null},
    {comment_id: 2, user_id: 19, comment_date: "05-22", comment_content: "还不错哦!很好看", parent_id: null},
    {comment_id: 3, user_id: 17, comment_date: "05-22", comment_content: "我也感觉蜡笔小新很好看", parent_id: "1"},
    {comment_id: 4, user_id: 14, comment_date: "05-25", comment_content: "我感觉机器猫更好看一点", parent_id: "3"},
    {comment_id: 5, user_id: 13, comment_date: "05-25", comment_content: "好看,已三连!", parent_id: null},
    {comment_id: 6, user_id: 21, comment_date: "06-05", comment_content: "你是机器猫的粉丝吗", parent_id: "4"},
    {comment_id: 7, user_id: 14, comment_date: "06-07", comment_content: "是的,我是机器猫的粉丝 test", parent_id: "6"},
    {comment_id: 8, user_id: 23, comment_date: "06-07", comment_content: "我更喜欢白嫖!", parent_id: "5"},
    {comment_id: 9, user_id: 25, comment_date: "06-07", comment_content: "你个白嫖怪", parent_id: "8"}
]

function fn(temp) {
    let arr1 = []
    for(let i=0; i<arr.length; i++) {
        if(arr[i].parent_id == temp) {
            arr1.push(arr[i])
            arr[i].child = fn(arr[i].comment_id)

        }
    }
    return arr1
}
let res = fn(null)
console.log(res)







// [
//     {comment_id: 1, user_id: 43, comment_date: "05-21", comment_content: "蜡笔小新很好看!", parent_id: null,child:[
//         {comment_id: 3, user_id: 17, comment_date: "05-22", comment_content: "我也感觉蜡笔小新很好看", parent_id: "1",child:[
//             {comment_id: 4, user_id: 14, comment_date: "05-25", comment_content: "我感觉机器猫更好看一点", parent_id: "3",child:[
//                 {comment_id: 6, user_id: 21, comment_date: "06-05", comment_content: "你是机器猫的粉丝吗", parent_id: "4"},
//             ]},
//         ]},
//     ]},
// ]
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